<?php
/**
 * Replace function is_callable()
 *
 * @category	PHP
 * @package	 PHP_Compat
 * @link		http://php.net/function.is_callable
 * @author	  Gaetano Giunta <giunta.gaetano@sea-aeroportimilano.it>
 * @version	 $Id: is_callable.php,v 1.3 2006/08/21 14:03:15 ggiunta Exp $
 * @since	   PHP 4.0.6
 * @require	 PHP 4.0.0 (true, false, etc...)
 * @todo		add the 3rd parameter syntax...
 */
if (!function_exists('is_callable')) {
	function is_callable($var, $syntax_only=false)
	{
		if ($syntax_only)
		{
			/* from The Manual:
			* If the syntax_only argument is TRUE the function only verifies
			* that var might be a function or method. It will only reject simple
			* variables that are not strings, or an array that does not have a
			* valid structure to be used as a callback. The valid ones are
			* supposed to have only 2 entries, the first of which is an object
			* or a string, and the second a string
			*/
			return (is_string($var) || (is_array($var) && count($var) == 2 && is_string(end($var)) && (is_string(reset($var)) || is_object(reset($var)))));
		}
		else
		{
			if (is_string($var))
			{
				return function_exists($var);
			}
			else if (is_array($var) && count($var) == 2 && is_string($method = end($var)))
			{
				$obj = reset($var);
				if (is_string($obj))
				{
					$methods = get_class_methods($obj);
					return (bool)(is_array($methods) && in_array(strtolower($method), $methods));
				}
				else if (is_object($obj))
				{
					return method_exists($obj, $method);
				}
			}
			return false;
		}
	}
}

?>